Orthogonal Frequency Division Multiplex (OFDM) is a multicarrier modulation scheme, where a data stream is transmitted using a number of multiplexed subcarriers. In OFDM multiple-input multiple-output (OFDM-MIMO) technology, multiple antennas are used to communicate OFDM data. According to some approaches to OFDM-MIMO, a wireless transmit/receive unit (WTRU) that is in communication with a base station may provide channel state information (CSI) to the base station to indicate properties of the air-link between the WTRU and the base station. In other approaches to OFDM-MIMO, a WTRU may provide CSI to a base station based on unprecoded channel state information reference signals (CSI-RS). While improvements have been made in recent years over previous approaches to the communication of CSI, further improvements to the generation, processing, and/or communication of CSI (such as but not limited to improvements that enhance the accuracy of CSI), may be needed.